TORONTO -- Candidates running for election in Canada's most populous city say an escalating dispute between Toronto and the Ontario government has plunged their campaigns into uncertainty and created a slew of logistical headaches as an October vote inches closer.

The situation in Toronto grew more chaotic this week after Premier Doug Ford announced Monday he'd use a constitutional provision to override a court decision that found his plan to cut the size of the city's council in the middle of an election violated candidates' and voters' freedom of expression rights.

Ford is expected to recall the legislature on Wednesday to invoke the notwithstanding clause and reintroduce Bill 5, which slashes Toronto's council from 47 to 25 wards.

The tussle between the province and the city has meant candidates have had to deal with a changing campaign structure over the past few weeks. For some, the latest twist has proved too much.

Chris Moise, who was among a number of parties who joined the court challenge against the province's council-cutting plan, said the latest developments have made him decide not to run in a 25-ward election.

"I was overwhelmed and overjoyed when the judge came back with a positive verdict yesterday," he said of the judgment that ordered a 47-ward election. "I went from having very high emotions to and vindication and a few hours later that changed. ... it takes its toll."

Moise said he's spent thousands of dollars and he and his team have been canvassing for months based on the 47-ward contest but those efforts appear to have been in vain.

"I followed the rules that were put in place, I put my best foot forward and to have this happen -- Bill 5 introduced two-thirds into the campaign threw us all off," he said. "I felt it was very unfair and unCanadian."

The entire situation has been hard on incumbents and newcomers alike, said Coun. Joe Cressy, who plans to seek re-election but has yet to officially register as a candidate.

"Candidates all have to, in this moment of uncertainty, live day-to-day but prepare for both," he said. "You prepare for 25 and 47."

The City of Toronto is holding a special council session on Thursday, after the provincial legislation passes, to see what options, if any, exist for the municipality to push back against Ford's plans, the mayor has said.

Cressy said he hopes the Thursday council session will provide greater clarity for candidates.

"It's important, in a public setting, for all our questions to be answered," he said. "For not only councillors, but frankly residents of our city to understand what the new rules are and what the new timelines are what the new wards are."

University of Toronto professor Nelson Wiseman said candidates will need to assume that the 25-ward structure will be in place because once Ontario uses the notwithstanding clause and passes Bill 5 again there are few options left for the city.

"It certainly is messy from a candidate's point of view," Wiseman said. "Voter turnout could be modest."

The city's election is set for Oct. 22.